My buddy worked as a welder on these:
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M20 in my JIG!
"Building a welding JIG first" - design process and thoughts
- Thread starter BartRidesEternal
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M20 in my JIG!
That's very impressive. And all I'm attempting is to make something a bit bigger and with more style then this as a reference frame. Infact I just sat down from gathering up some old conduit and PVC pipes and some scrap flat bars to put together a mock-up of what I want to do before I start chopping up old bike frames. I'm really glad I don't get threatened or overwhelmed when see a masterpiece and thinking " couldn't pull that off.". Lol. I'm confident that with material available and a clear sense of my own limited knowledge and ability that I'll do just fine for a 1st bicycle fabrication or rearrangement. His and your work are inspiring and I've already picked up on a couple things to look out for that had not accured to me. Thanks again.
This is the frame I'm using as a sort of reference. It's a small 1976 24" trike.
This is the frame I'm using as a sort of reference. It's a small 1976 24" trike.
Very cool frame Ed!
Thank you, I really appreciate your reply.
@kingfish254 showed a picture here from a bicycle called 'Stardust'. I instantly thought how did he do that? Tight bends, alignment... skills!
Regarding your frame:
You could utilize the front part of a larger bike and build the rear. Alignment from the bottom bracket rearward.
Or use a standard frame and just add that big diameter rear tube including the trike dropouts.
So many ways to build
As of now I've settled on using that frame.just for reference. After all it is a 48 year old single year design bike and other then the rims and spokes I still have everything for it. And I think it will go smoother and have a cleaner finish built from scratch rather than chopping this up and changing it. I can't draw to save my life so I made a giant sized tinker toy style mock-up so I could see how it looked not in my mind. I'm making the wheel base about a foot shorter and decided on a step up king and queen motorcycle seat. Over all I'm satisfied with the rough draft.Very cool frame Ed!
Thank you, I really appreciate your reply.
@kingfish254 showed a picture here from a bicycle called 'Stardust'. I instantly thought how did he do that? Tight bends, alignment... skills!
Regarding your frame:
You could utilize the front part of a larger bike and build the rear. Alignment from the bottom bracket rearward.
Or use a standard frame and just add that big diameter rear tube including the trike dropouts.
So many ways to build
The picture below shows how I plan on 2 bikes top bars then welded onto the side of the head tube and the bottom bars will come together at the back of the bottom bracket and the single tube straight up the the bottom of the head tube. The outside rear stays I'll keep , bend and possibly lengthen. Still have a couple other ideas for that . Looking at a heavier then stock 40-44 inch wide rear differential and axels.
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I'm also working out in my head the best way to get some type of rear suspension, my brain is thinking small air bags and possibly adding spindles and u-joints to the axels so I can have some camber for higher speeds when I break down later and add that 3000w electric motor to it. A neighbor already brought over a 10hp horizontal shaft Tecumseh motor last night.Very cool frame Ed!
Thank you, I really appreciate your reply.
@kingfish254 showed a picture here from a bicycle called 'Stardust'. I instantly thought how did he do that? Tight bends, alignment... skills!
Regarding your frame:
You could utilize the front part of a larger bike and build the rear. Alignment from the bottom bracket rearward.
Or use a standard frame and just add that big diameter rear tube including the trike dropouts.
So many ways to build
Some updates:
I ordered and designed all remaining parts for the JIG.
The idea is to clamp it with a simple glueing clamp. Strong, tight grip and enough elasticity to retain that grip over time.
The orange rounds on the photo are tube diameters similated. 25mm and 45mm thickness variables.
Its a 10mm thick 6062 aluminium angle profile.
I ordered and designed all remaining parts for the JIG.
- I will use a standard M10 threaded rod for the rear dropout. Or a Shimano CB-E110 shaft (M10x1 threads).
- Cones for the seattube and headtube are in!
- Angular profile (50x50x10) for the top seat tube is ordered.
- Tube clamp for the seat tube near the bottom bracket:
The idea is to clamp it with a simple glueing clamp. Strong, tight grip and enough elasticity to retain that grip over time.
The orange rounds on the photo are tube diameters similated. 25mm and 45mm thickness variables.
Its a 10mm thick 6062 aluminium angle profile.
In regards to building my own designed frames in the JIG: I had a little luck yesterday. A guy on a online marketplace was selling brand new, and complete shaft drives for less than 1/10 of the original price.
The box with five complete sets.
Dropout on the left. Bottom Bracket on the right, complete with locknut, square tapered shaft and locknut.
Two pictures above: threaded sprocket.
Pictures above: Three slotted sprocket.
The larger diameter is nearly the same as a US bottom bracket pot. Awesome!
Options and ideas!
The box with five complete sets.
Dropout on the left. Bottom Bracket on the right, complete with locknut, square tapered shaft and locknut.
Two pictures above: threaded sprocket.
Pictures above: Three slotted sprocket.
The larger diameter is nearly the same as a US bottom bracket pot. Awesome!
Options and ideas!
Nice find. I’ve never found those for sale except for production levels. The hard part might be finding compatible hubs, which I also have not had success.
But if I understand, the threaded/splined sprockets inteface with the drive gear on one side and the threaded hub/three-splined IGH on the other? No wonder I failed! lol.
Should be able to make a bomb proof, low maintenance cruiser or town bike. No chain to dirty the dockers!
But if I understand, the threaded/splined sprockets inteface with the drive gear on one side and the threaded hub/three-splined IGH on the other? No wonder I failed! lol.
Should be able to make a bomb proof, low maintenance cruiser or town bike. No chain to dirty the dockers!
MattiThundrrr
Rattus All Terrainus
Congrats, man! That's a great deal! Can't wait to see what comes out of elBarto's shop next!
The welding JIG is near completion. Waiting for a few materials to arrive which I can throw in the lathe.
After the JIG is completed, I already have a project waiting to test out the JIG.
While testing the JIG, I am thinking about doing a class course in brazing. I have my eye on a dutch frame building company that might be open to give a class course.
Simultaneously, I will be looking at notching and bending machines. A bending machine like in: A tubing rolling machine.
The Bottom Bracket bracket is done and can be assembled on the JIG:
In the meantime I slightly changed the previous bike geometry. A bike that is beautiful and fun to ride or commute.
Design philosophy for a 'practicool' cruiser bike (having some experience) being:
Fill in the lines and geometry you like here! That single little line next to/above the rear wheel is the top of the seat tube.
Not on the drawing: Fork offset is 60mm.
After the JIG is completed, I already have a project waiting to test out the JIG.
While testing the JIG, I am thinking about doing a class course in brazing. I have my eye on a dutch frame building company that might be open to give a class course.
Simultaneously, I will be looking at notching and bending machines. A bending machine like in: A tubing rolling machine.
The Bottom Bracket bracket is done and can be assembled on the JIG:
In the meantime I slightly changed the previous bike geometry. A bike that is beautiful and fun to ride or commute.
Design philosophy for a 'practicool' cruiser bike (having some experience) being:
- Long cruiser bike with a 'belly mounted' bottom bracket, like the Basman or Ruff Cycles Porucho for example.
- BUT the bottom bracket- to ground clearance AND the bottom bracket- to front tire clearance enough to ride comfortably without hitting the ground and/or front wheel.
- 26x3.0" wheels.
- Low seat, the seat deck being inches above the top of the rear wheel.
Fill in the lines and geometry you like here! That single little line next to/above the rear wheel is the top of the seat tube.
Not on the drawing: Fork offset is 60mm.
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Looks like you’re dialing it in. Some of the best advice I received was to study what has been done before -and works- and stay within that range of geometry. You have your eye on ground clearance and tire/toe interference, which is a problem on some “more show than go” bikes, so I think you are on the right track.
Thank you John!
I experienced that issue with my Basman and Ruff Cycles Porucho bike. But I do love their looks, so I'll find something in between.
My geometry with 3D models: Bottom Bracket shell, Wheels and a headtube shell.
The rest is open for a free sketch
Hi guys.
Now I start looking at other tooling like:
Thanks to @deven_science I learned about the 'Harbor Freight Roller' (thank you!).
Tooling gives you options.
Since I am just starting in the fabrication field and having to pay attention to the budget, I'll have to think smart about the tube diameters I am using, or else I am buying all sorts of sizes randomly.
Material:
25CrMo4 (CroMoly) tubing is easy to come-by and I will use that first.
I intend to create flowing shapes, so no extreme tight bends in my first sessions. CroMoly suffices.
From a frame-perspective:
Tube diameter used for a frame-section:
Why did I choose these diameters you wonder?
Ideally, I would love more options. But I have to start somewhere and let it grow.
22mm is a diameter that is used a lot in bicycles: Also seat tubing and handlebars. This gives me options to fabricate in that field too.
28mm also is a common diameter which gives me multiple options to work with as opposed to 30mm.
I am still thinking about 35 or 40mm for the downtube.
A 1" headtube is usually about 34mm in outer diameter.
And a 1 1/8" about 37mm in outer diameter.
In that sense and looks, a 35 might be more appealing to finish and look at. Even tough you can narrow/pinch a tube a little bit to get an oval shape...
Let me know if you have suggestions/ideas or advice.
Pictures soon.
Thanks!
- I finished the welding JIG. Just a few last things to adjust and assemble.
- I bought an tubing roller. I nearly bought a new one, but then I found one on a marketplace for 1/3 of the price.
Now I start looking at other tooling like:
- Tube Notcher.
- Rollers for specific tube diameters.
- A bending machine (mainly for chain- and seatstays).
Thanks to @deven_science I learned about the 'Harbor Freight Roller' (thank you!).
Tooling gives you options.
Since I am just starting in the fabrication field and having to pay attention to the budget, I'll have to think smart about the tube diameters I am using, or else I am buying all sorts of sizes randomly.
Material:
25CrMo4 (CroMoly) tubing is easy to come-by and I will use that first.
I intend to create flowing shapes, so no extreme tight bends in my first sessions. CroMoly suffices.
From a frame-perspective:
Tube diameter used for a frame-section:
- Top tube: 28mm, 35mm.
- Down tube: 35mm (or 40mm?).
- Seat tube: 28mm.
- Seat stays: 22mm.
- Chain stays: 22mm.
- Tubing roller extra rollers: 22mm, 28mm, 35mm.
- Hand bending machine: 22mm.
Why did I choose these diameters you wonder?
Ideally, I would love more options. But I have to start somewhere and let it grow.
22mm is a diameter that is used a lot in bicycles: Also seat tubing and handlebars. This gives me options to fabricate in that field too.
28mm also is a common diameter which gives me multiple options to work with as opposed to 30mm.
I am still thinking about 35 or 40mm for the downtube.
A 1" headtube is usually about 34mm in outer diameter.
And a 1 1/8" about 37mm in outer diameter.
In that sense and looks, a 35 might be more appealing to finish and look at. Even tough you can narrow/pinch a tube a little bit to get an oval shape...
Let me know if you have suggestions/ideas or advice.
Pictures soon.
Thanks!
Thanks for your advice, I will do that!
I am thinking about buying this one:
RV-3 Rotary Tube Notcher
It is expensive compared to some, but the rotary function gives me a lot of options and adjustments.
Even out-of-centre notching made easy.
American Made
That tube notcher should serve quite well.
For hole saws, I reccomend these fine tooth options from Metal-Guru. https://metal-guru.com/collections/tools-cutting
Way better than anything in the hardware stores and a wide variety of sizes.
Though shipping across the pond may be impractical. Perhaps you can find a more local supplier. The finer teeth make a tremendous difference.
*edit… made in Germany, so, likely an EU supplier available.
For hole saws, I reccomend these fine tooth options from Metal-Guru. https://metal-guru.com/collections/tools-cutting
Way better than anything in the hardware stores and a wide variety of sizes.
Though shipping across the pond may be impractical. Perhaps you can find a more local supplier. The finer teeth make a tremendous difference.
*edit… made in Germany, so, likely an EU supplier available.
That is a great link, lots of framebuilding parts and knowledge. Thanks John!
I will find the saws in Germany. Definitely!
Very nice!
My own design tube clamp came to life.
Its made for the lower part of a seat tube, since the bottom bracket is located in the belly instead of in line with the seat tube.
The two screws can hold it firmly on the JIG in any position. Reason is, I wanted to be able to use it with a curved seat tube, not only straight seat tubes.
Attachments
That roller looks like an improvement over the HF model.
